SHARE CAPITAL (Detail) - Stock Options Outstanding - $ / shares	12 Months Ended
Apr. 30, 2020	Apr. 30, 2019
Share-based Payment Arrangement [Abstract]
Outstanding, Beginning	5,625,000	6,405,000
Outstanding, Weighted Average Exercise Price, Beginning	$ 0.26
Granted		1,450,000
Exercised		(600,000)
Expired	(2,275,000)	(1,630,000)
Forfeited	(400,000)
Granted, Weighted Average Exercise Price		$ 0.25
Exercised, Weighted Average Exercise Price		0.10
Expired, Weighted Average Exercise Price	$ 0.25	0.17
Forfeited, Weighted Average Exercise Price	0.30
Outstanding, Weighted Average Exercise Price	$ 0.26	$ 0.26
Outstanding, End	2,950,000	5,625,000
Exercisable, Weighted Average Exercise Price	$ 0.26
Exercisable	1,700,000

No definition available.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Gross number of share options (or share units) granted during the period.

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No definition available.

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Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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No definition available.

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Number of share options (or share units) exercised during the current period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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